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1.
Radmila Faizova Farzaneh Fadaei‐Tirani Rizlan Bernier‐Latmani Marinella Mazzanti 《Angewandte Chemie (International ed. in English)》2020,59(17):6756-6759
Reduction of uranyl(VI) to UV and to UIV is important in uranium environmental migration and remediation processes. The anaerobic reduction of a uranyl UVI complex supported by a picolinate ligand in both organic and aqueous media is presented. The [UVIO2(dpaea)] complex is readily converted into the cis‐boroxide UIV species via diborane‐mediated reductive functionalization in organic media. Remarkably, in aqueous media the uranyl(VI) complex is rapidly converted, by Na2S2O4, a reductant relevant for chemical remediation processes, into the stable uranyl(V) analogue, which is then slowly reduced to yield a water‐insoluble trinuclear UIV oxo‐hydroxo cluster. This report provides the first example of direct conversion of a uranyl(VI) compound into a well‐defined molecular UIV species in aqueous conditions. 相似文献
2.
Qing‐Jiang Pan Dr. Grigory A. Shamov Dr. Georg Schreckenbach Prof. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(7):2282-2290
On the basis of uranyl complexes reacting with a polypyrrolic ligand (H4L), we explored structures and reaction energies of a series of new binuclear uranium(VI) complexes using relativistic density functional theory. Full geometry optimizations on [(UO2)2(L)], in which two uranyl groups were initially placed into the pacman ligand cavity, led to two minimum‐energy structures. These complexes with cation–cation interactions (CCI) exhibit unusual coordination modes of uranyls: one is a T‐shaped ( T ) skeleton formed by two linear uranyls {Oexo?U2?Oendo→U1(?Oexo)2}, and another is a butterfly‐like ( B ) unit with one linear uranyl coordinating side‐by‐side to a second cis‐uranyl. The CCI in T was confirmed by the calculated longest distance and lowest stretching vibrational frequency of U2?Oendo among the four U?O bonds. Isomer B is more stable than T , for which experimental tetrameric analogues are known. The formation of B and T complexes from the mononuclear [(UO2)(H2L)(thf)] ( M ) was found to be endothermic. The further protonation and dehydration of B and T are thermodynamically favorable. As a possible product, we have found a trianglelike binuclear uranium(VI) complex having a O?U?O?U?O unit. 相似文献
3.
Dr. Clément Falaise Dr. Christophe Volkringer Dr. Christoph Hennig Dr. Thierry Loiseau 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(46):16654-16664
The ex‐situ qualitative study of the kinetic formation of the poly‐oxo cluster U38, has been investigated after the solvothermal reaction. The resulting products have been characterized by means of powder XRD and scanning electron microscopy (SEM) for the solid phase and UV/Vis, X‐ray absorption near edge structure (XANES), extended X‐ray absorption fine structure (EXAFS), and NMR spectroscopies for the supernatant liquid phase. The analysis of the different synthesis batches, stopped at different reaction times, revealed the formation of spherical crystallites of UO2 from t=3 h, after the formation of unknown solid phases at an early stage. The crystallization of U38 occurred from t=4 h at the expense of UO2, and is completed after t=8 h. Starting from pure uranium(IV) species in solution (t=0–1 h), oxidation reactions are observed with a UIV/UVI ratio of 70:30 for t=1–3 h. Then, the ratio is inversed with a UIV/UVI ratio of 25/75, when the precipitation of UO2 occurs. Thorough SEM observations of the U38 crystallites showed that the UO2 aggregates are embedded within. This may indicate that UO2 acts as reservoir of uranium(IV), for the formation of U38, stabilized by benzoate and THF ligands. During the early stages of the U38 crystallization, a transient crystallized phase appeared at t=4 h. Its crystal structure revealed a new dodecanuclear moiety (U12), based on the inner hexanuclear core of {U6O8} type, decorated by three additional pairs of dinuclear U2 units. The U12 motif is stabilized by benzoate, oxalates, and glycolate ligands. 相似文献
4.
Anton V. Savchenkov Anna V. Vologzhanina Larisa B. Serezhkina Denis V. Pushkin Viktor N. Serezhkin 《Acta Crystallographica. Section C, Structural Chemistry》2013,69(7):721-726
FT–IR spectroscopy and single‐crystal X‐ray structure analysis were used to characterize the discrete neutral compound diaquadioxidobis(n‐valerato‐κ2O,O′)uranium(VI), [UO2(C4H9COO)2(H2O)2], (I), and the ionic compound potassium dioxidotris(n‐valerato‐κ2O,O′)uranium(VI), K[UO2(C4H9COO)3], (II). The UVI cation in neutral (I) is at a site of 2/m symmetry. Potassium salt (II) has two U centres and two K+ cations residing on twofold axes, while a third independent formula unit is on a general position. The ligands in both compounds were found to suffer severe disorder. The FT–IR spectroscopic results agree with the X‐ray data. The composition and structure of the ionic potassium uranyl valerate are similar to those of previously reported potassium uranyl complexes with acetate, propionate and butyrate ligands. Progressive lengthening of the alkyl groups in these otherwise similar compounds was found to have an impact on their structures, including on the number of independent U and K+ sites, on the coordination modes of some of the K+ centres and on the minimum distances between U atoms. The evolution of the KUO6 frameworks in the four homologous compounds is analysed in detail, revealing a new example of three‐dimensional topological isomerism in coordination compounds of UVI. 相似文献
5.
P. Giridhar K. A. Venkatesan T. G. Srinivasan P. R. Vasudeva Rao 《Journal of Radioanalytical and Nuclear Chemistry》2005,265(1):31-38
Summary A systematic study on the extraction of U(VI) from nitric acid medium by tri-n-butylphosphate (TBP) dissolved in a non-traditional diluent namely 1-butyl-3-methylimidazolium hexafluorophosphate (bmimPF6) ionic liquid (IL) is reported. The results are compared with those obtained using TBP/n-dodecane (DD). The distribution ratio for the extraction of U(VI) from nitric acid by 1.1M TBP/bmimPF6 increases with increasing nitric acid concentration. The U(VI) distribution ratios are comparable in the nitric acid concentration range of 0.01M to 4M, to the ratios measured using 1.1M TBP/DD. In contrast to the extraction behavior of TBP/DD, the D values continued to increase with the increase in the concentration of nitric acid above 4.0M. The stoichiometry of uranyl solvate extracted by 1.1M TBP/IL is similar to that of TBP/DD system, wherein two molecules of TBP are associated with one molecule of uranyl nitrate in the organic phase. Ionic liquid alone also extracts uranium from nitric acid, albeit to a small extent. The exothermic enthalpy accompanying the extraction of U(VI) in TBP/bmimPF6 decreases with increasing nitric acid and with TBP concentrations. 相似文献
6.
Guy M. Jones Prof. Polly L. Arnold Dr. Jason B. Love 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(31):10287-10294
Simple and versatile routes to the functionalization of uranyl‐derived UV–oxo groups are presented. The oxo‐lithiated, binuclear uranium(V)–oxo complexes [{(py)3LiOUO}2(L)] and [{(py)3LiOUO}(OUOSiMe3)(L)] were prepared by the direct combination of the uranyl(VI) silylamide “ate” complex [Li(py)2][(OUO)(N”)3] (N”=N(SiMe3)2) with the polypyrrolic macrocycle H4L or the mononuclear uranyl (VI) Pacman complex [UO2(py)(H2L)], respectively. These oxo‐metalated complexes display distinct U? O single and multiple bonding patterns and an axial/equatorial arrangement of oxo ligands. Their ready availability allows the direct functionalization of the uranyl oxo group leading to the binuclear uranium(V) oxo–stannylated complexes [{(R3Sn)OUO}2(L)] (R=nBu, Ph), which represent rare examples of mixed uranium/tin complexes. Also, uranium–oxo‐group exchange occurred in reactions with [TiCl(OiPr)3] to form U‐O? C bonds [{(py)3LiOUO}(OUOiPr)(L)] and [(iPrOUO)2(L)]. Overall, these represent the first family of uranium(V) complexes that are oxo‐functionalised by Group 14 elements. 相似文献
7.
A. S. Kanekar P. N. Pathak P. K. Mohapatra V. K. Manchanda 《Journal of Radioanalytical and Nuclear Chemistry》2010,283(3):789-796
Extraction of uranium from tissue paper, synthetic soil, and from its oxides (UO2, UO3 and U3O8) was carried out using supercritical carbon dioxide modified with methanol solutions of extractants such as tri-n-butyl phosphate (TBP) or N,N-dihexyl octanamide (DHOA). The effects of temperature, pressure, extractant/nitric acid (nitrate) concentration, and of hydrogen
peroxide on uranium extraction were investigated. The dissolution and extraction of uranium in supercritical CO2 modified with TBP, from oxide samples followed the order: UO3 ≫ UO2 > U3O8. Addition of hydrogen peroxide in the modifier solution enhanced the dissolution/extraction of uranium in dynamic mode. DHOA
appeared better than TBP for recovery of uranium from different oxide samples. Similar enhancement in uranium extraction was
observed in static mode experiments in the presence of hydrogen peroxide. Uranium estimation in the extracted fraction was
carried out by spectrophotometry employing 2-(5-bromo-2-pyridylazo)-5-diethylaminophenol (Br-PADAP) as the chromophore. 相似文献
8.
E. S. Stoynov V. A. Mikhailov V. G. Torgov T. V. Us 《Journal of Structural Chemistry》1994,35(6):809-816
This paper reprots of31P NMR and IR studies of the interaction of tributyl phosphate (TBP) and di-n-octyl sulfoxide (DOSO) with polymer molecules
of uranyl di-2-ethylhexyl phosphate (UO2X2)p (I) in C6H6 sulutions. Detailed interpretations of the31P NMR spectra and the vas(POO) IR bands and determination of the fraction of nonequivalent phosphorus atoms of X− anions and uranium (VI) atoms as well as the concentration of U(VI)-bonded TBP in I have shown that only a single TBP or
DOSO molecule is coordinated to the uranium atoms of polymer I at CTBP=0.1–2 M or CDOSO=0.1–0.5 M. In the case of 100% TBP, two TBP molecules are coordinated to some U(VI) atoms. Distribution of TBP (DOSO) molecules
along the polymer chain agrees with the mean statistical value. The portion of terminal chalate POO-groups of X− anions is determined. The dependence of the degree of (UO2X2)p·nL (L=TBP, DOSO) polymerization on CL is obtained. Saturation of solutions with water only slightly affects the terminal POO-groups and has no effects on the distribution
of L along the polymer chain of I.
Institute of Catalysis, Siberian Branch, Russian Academy of Sciences. Translated fromZhurnal Strukturnoi Khimii, Vol. 35, No. 6, pp. 66–73, November–December, 1994.
Translated by K. Shaposhnikova 相似文献
9.
S. Biswas P. N. Pathak D. K. Singh S. B. Roy V. K. Manchanda 《Journal of Radioanalytical and Nuclear Chemistry》2011,289(2):557-564
The extraction of U(VI) from sulphate medium with 2-ethylhexyl phosphonic acid-mono-2-ethylhexyl ester (PC88A, H2A2 in dimeric form) in n-dodecane has been investigated under varying concentrations of sulphuric acid and uranium. Slope analysis of uranium (VI)
distribution data as a function of PC88A concentration suggests the formation of monomeric species, viz. UO2(HA2)2. This observation was further supported by the mathematical expression obtained during non-linear least square regression
analysis of U(VI) distribution data correlating the percentage extraction (%E) and the acidity (H
i). A mathematical model correlating the experimental distribution ratio values of U(VI) (D
U) with initial acidity (H
i) and initial uranium concentrations (C
i) was developed:
D\textU = 12.98( ±0.90)/{ C\texti - 0.75( ±0.05) ×[ H\texti ]2 } D_{\text{U}} = 12.98( \pm 0.90)/\left\{ {C_{\text{i}}^{ - 0.75( \pm 0.05)} \times \left[ {H_{\text{i}} } \right]^{2} } \right\} . This expression can be used to predict the concentration of uranium in organic as well as in aqueous phase at any C
i and H
i. The extraction data were used to calculate the conditional extraction constant (K
ex) values at different acidities (2–7 M H+), uranium (0.02–0.1 M) and PC88A (0.2–0.6 M) concentrations. These studies were also extended for the extraction of U(VI)
using synergistic mixtures of PC88A and TOPO from sulphate medium. 相似文献
10.
Pierre Thury Hiroyuki Takemura 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(10):m384-m386
The title complex, diaquadipyridinelithium (N‐methyl‐p‐tert‐butyldihomoammoniocalix[4]arene‐κ4O)dioxouranium(VI) tripyridine solvate monohydrate, [Li(C5H5N)2(H2O)2][UO2(C46H58NO4)]·3C5H5N·H2O, contains an `internal' tetraphenoxide‐coordinated uranyl complex of the macrocycle, in which the protonated N atom is involved in an intramolecular hydrogen bond with the uranyl oxo group located in the cavity. The Li+ ion is in a tetrahedral environment and its two water ligands are involved in hydrogen bonds with two phenoxide O atoms, two pyridine molecules and one water molecule. This arrangement is compared with those obtained previously for other homoazacalixarenes and also for homooxacalixarenes in the presence of alkali metal hydroxides. 相似文献
11.
Template‐Free Synthesis and Mechanistic Study of Porous Three‐Dimensional Hierarchical Uranium‐Containing and Uranium Oxide Microspheres
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Dr. Lin Wang Dr. Ran Zhao Dr. Cong‐zhi Wang Dr. Li‐yong Yuan Dr. Zhan‐jun Gu Dr. Cheng‐liang Xiao Dr. Shu‐ao Wang Dr. Xin‐wei Wang Prof. Yu‐liang Zhao Prof. Zhi‐fang Chai Dr. Wei‐qun Shi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(39):12655-12662
A novel type of uranium‐containing microspheres with an urchin‐like hierarchical nano/microstructure has been successfully synthesized by a facile template‐free hydrothermal method with uranyl nitrate hexahydrate, urea, and glycerol as the uranium source, precipitating agent, and shape‐controlling agent, respectively. The as‐synthesized microspheres were usually a few micrometers in size and porous inside, and their shells were composed of nanoscale rod‐shaped crystals. The growth mechanism of the hydrothermal reaction was studied, revealing that temperature, ratios of reactants, solution pH, and reaction time were all critical for the growth. The mechanism study also revealed that an intermediate compound of 3 UO3?NH3?5 H2O was first formed and then gradually converted into the final hydrothermal product. These uranium‐containing microspheres were excellent precursors to synthesize porous uranium oxide microspheres. With a suitable calcination temperature, very uniform microspheres of uranium oxides (UO2+x, U3O8, and UO3) were successfully synthesized. 相似文献
12.
Isolation of a Star‐Shaped Uranium(V/VI) Cluster from the Anaerobic Photochemical Reduction of Uranyl(VI)
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Lucile Chatelain Sarah White Dr. Rosario Scopelliti Prof. Marinella Mazzanti 《Angewandte Chemie (International ed. in English)》2016,55(46):14325-14329
Actinide oxo clusters are an important class of compounds due to their impact on actinide migration in the environment. The photolytic reduction of uranyl(VI) has potential application in catalysis and spent nuclear fuel reprocessing, but the intermediate species involved in this reduction have not yet been elucidated. Here we show that the photolysis of partially hydrated uranyl(VI) in anaerobic conditions leads to the reduction of uranyl(VI), and to the incorporation of the resulting UV species into the stable mixed‐valent star‐shaped UVI/UV oxo cluster [U(UO2)5(μ3‐O)5(PhCOO)5(Py)7] ( 1 ). This cluster is only the second example of a UVI/UV cluster and the first one associating uranyl groups to a non‐uranyl(V) center. The UV center in 1 is stable, while the reaction of uranyl(V) iodide with potassium benzoate leads to immediate disproportionation and formation of the U12IVU4VO24 cluster {[K(Py)2]2[K(Py)]2[U16O24(PhCOO)24(Py)2]} ( 5 ). 相似文献
13.
Radmila Faizova Dr. Farzaneh Fadaei-Tirani Prof. Dr. Rizlan Bernier-Latmani Prof. Dr. Marinella Mazzanti 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(17):6822-6825
Reduction of uranyl(VI) to UV and to UIV is important in uranium environmental migration and remediation processes. The anaerobic reduction of a uranyl UVI complex supported by a picolinate ligand in both organic and aqueous media is presented. The [UVIO2(dpaea)] complex is readily converted into the cis-boroxide UIV species via diborane-mediated reductive functionalization in organic media. Remarkably, in aqueous media the uranyl(VI) complex is rapidly converted, by Na2S2O4, a reductant relevant for chemical remediation processes, into the stable uranyl(V) analogue, which is then slowly reduced to yield a water-insoluble trinuclear UIV oxo-hydroxo cluster. This report provides the first example of direct conversion of a uranyl(VI) compound into a well-defined molecular UIV species in aqueous conditions. 相似文献
14.
K. Shakir Sh. G. Beheir M. Aziz 《Journal of Radioanalytical and Nuclear Chemistry》1992,162(2):371-380
The effect of added TBP on the extraction of uranium(VI) with a solution of di-(2-ethylhexyl)-phosphoric acid (HDEHP) in o-dichlorobenzene from nitric acid solutions has been investigated at varying concentrations of nitric acid, HDEHP, TBP and uranium(VI). The mechanism of the synergistic effect of TBP is discussed on the basis of the results and can be summarized in the following equation: UO
2(aq)
2+
+0.67(HX)3(o)+2TBP(o)UO2X2·2TBP(o)+2H
(aq)
+
where HX denotes HDEHP and the HDEHP loaded on the foam is trimerized. 相似文献
15.
Dr. Prasanta K. Mohapatra Arijit Sengupta Mudassir Iqbal Dr. Jurriaan Huskens Dr. Willem Verboom 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(9):3230-3238
Two new diglycolamide‐based task‐specific ionic liquids (DGA? TSILs) were evaluated for the extraction of actinides and lanthanides from acidic feed solutions. These DGA? TSILs were capable of exceptionally high extraction of trivalent actinide ions, such as Am3+, and even higher extraction of the lanthanide ion, Eu3+ (about 5–10 fold). Dilution of the DGA? TSILs in an ionic liquid, C4mim+ ? NTf2?, afforded reasonably high extraction ability, faster mass transfer, and more efficient stripping of the metal ion. The nature of the extracted species was studied by slope analysis, which showed that the extracted species contained one NO3? anion, along with the participation of two DGA? TSIL molecules. Time‐resolved laser fluorescence spectroscopy (TRLFS) analysis showed a strong complexation with no inner‐sphere water molecule in the EuIII? DGA? TSIL complexes in the presence and absence of C4mim+ ? NTf2? as the diluent. The very high radiolytic stability of DGA? TSIL 6 makes it one of the most‐efficient solvent systems for the extraction of actinides under acidic feed conditions. 相似文献
16.
K. V. Chetty P. M. Mapara Rajendra Swarup S. K. Patil 《Journal of Radioanalytical and Nuclear Chemistry》1988,121(1):149-159
The extraction of U(VI) by mixtures of HTTA and TBP from aqueous thiocyanate medium has been studied. From the data obtained it was observed that the predominant uranium species extracted, causing synergic enhancement in the extraction of U(VI), is UO2(SCN)TTA · 2TBP when benzene and cyclohexane are used as diluents, and that at a very low concentration of TBP the contribution of additional species, viz. UO2(TTA)2 · TBP becomes significant. With chloroform as diluent, however, both of these species are contributing to the synergic enhancement. The extraction of a quaternary uranium species, UO2(SCN)TTA · 2TBP, involving the participation of the aqueous anion is thus established. Equilibrium constants for the various extraction equilibria involved are calculated. 相似文献
17.
Lionel Salmon Pierre Thury Michel Ephritikhine Bernardo Masci 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(1):m27-m29
The title compound, [UO2(C33H38N2O2)2](CF3SO3)2·2C5H5N, has been obtained by reaction of UIV trifluoromethanesulfonate with p‐tert‐butyltetrahomodioxacalix[4]arene in pyridine. The uranyl ion lies on an inversion centre and is bound to two O atoms from each diphenoxide ligand, which gives the usual square‐planar equatorial environment. The zwitterionic diphenoxide species results from nucleophilic attack by pyridine on the benzylic ether C atoms of the homooxacalixarene, assisted by initial U coordination to the ether groups, with subsequent metal oxidation giving the uranyl moiety. 相似文献
18.
《Acta Crystallographica. Section C, Structural Chemistry》2018,74(3):366-371
The interaction between the uranyl cation, (UO2)2+, and organic species is of interest due to the potential applications of the resulting compounds with regard to nuclear waste disposal and nuclear fuel reprocessing. The hydrothermal reaction of various uranyl compounds with flexible zwitterionic 1,1′‐[1,4‐phenylenebis(methylene)]bis(pyridin‐1‐ium‐4‐carboxylate) dihydrochloride (Bpmb·2HCl) in deionized water containing drops of H2SO4 resulted in the formation of a novel two‐dimensional uranyl coordination polymer, namely poly[tetraoxido{μ2‐1,1′‐[1,4‐phenylenebis(methylene)]bis(pyridin‐1‐ium‐4‐carboxylate)}di‐μ3‐sulfato‐diuranium(VI)], [(UO2)2(SO4)2(C20H16N2O4)]n, (1). Single‐crystal X‐ray diffraction reveals that this coordination polymer exhibits a layered arrangement and the (UO2)2+ centre is coordinated by five equatorial O atoms. The structure was further characterized by FT–IR spectroscopy, powder X‐ray diffraction (PXRD) and thermogravimetric analysis (TGA). The polymer shows high thermal stability up to 696 K. Furthermore, the photoluminescence properties of (1) has also been studied, showing it to exhibit a typical uranyl fluorescence. 相似文献
19.
Dr. Eitan Tiferet Dr. Adrià Gil Dr. Carles Bo Dr. Tatiana Y. Shvareva Dr. May Nyman Dr. Alexandra Navrotsky 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(13):3646-3651
Nanoscale uranyl peroxide clusters containing UO22+ groups bonded through peroxide bridges to form polynuclear molecular species (polyoxometalates) exist both in solution and in the solid state. There is an extensive family of clusters containing 28 uranium atoms (U28 clusters), with an encapsulated anion in the center, for example, [UO2(O2)3?x(OH)x4?], [Nb(O2)43?], or [Ta(O2)43?]. The negative charge of these clusters is balanced by alkali ions, both encapsulated, and located exterior to the cluster. The present study reports measurement of enthalpy of formation for two such U28 compounds, one of which is uranyl centered and the other is peroxotantalate centered. The [(Ta(O2)4]‐centered U28 capsule is energetically more stable than the [(UO2)(O2)3]‐centered capsule. These data, along with our prior studies on other uranyl–peroxide solids, are used to explore the energy landscape and define thermochemical trends in alkali–uranyl–peroxide systems. It was suggested that the energetic role of charge‐balancing alkali ions and their electrostatic interactions with the negatively charged uranyl–peroxide species is the dominant factor in defining energetic stability. These experimental data were supported by DFT calculations, which agree that the [(Ta(O2)4]‐centered U28 capsule is more stable than the uranyl‐centered capsule. Moreover, the relative stability is controlled by the interactions of the encapsulated alkalis with the encapsulated anion. Thus, the role of alkali‐anion interactions was shown to be important at all length scales of uranyl–peroxide species: in both comparing clusters to clusters; and clusters to monomers or extended solids. 相似文献
20.
Li Lin Yang Yan-Zhao Zeng Shan Zhu Tao Sun Si-Xiu 《Journal of Radioanalytical and Nuclear Chemistry》2005,266(2):355-359
Summary The synergistic extraction of uranium(VI) from aqueous nitric acid solution with a mixture of tri-n-butyl phosphate (TBP)
and i-butyldodecylsulfoxide (BDSO) in toluene was investigated. The effects of the concentrations of extractant, nitric acid,
sodium nitrate and sodium oxalate on the distribution ratios of uranium(VI) have been studied. The values of enthalpy change
for the extraction reactions with BDSO, TBP and a mixture of TBP and BDSO in toluene were -23.2±0.8 kJ/mol, -29.2±1.4 kJ/mol
and -30.6±0.6 kJ/mol, respectively. It has been found that the maximum synergistic extraction effect occurs when the molar
ratio of TBP to BDSO is close to 1. The composition of the complex of the synergistic extraction is UO2(NO3)2 . BDSO . TBP. 相似文献